The greater complexity of trade, the larger variety of commodities, the increased specialization in production and distribution, the growth of "a science of adulteration" have immensely increased the advantage which the professional salesman possesses over the amateur customer.

Hence the growth of goods meant not for use but for sale--jerry-built houses, adulterated food, sham cloth and leather, botched work of every sort, designed merely to pass muster in a hurried act of sale.

To such a degree of refinement have the arts of deception been carried that the customer is liable to be tricked and duped at every turn.

It is not that he foolishly prefers to buy a bad article at a low price, but that he cannot rely upon his judgment to discriminate good from bad quality; he therefore prefers to pay a low price because he has no guarantee that by paying more he will get a better article.

It is this fact, and not a mania for cheapness, which explains the flooding of the market with bad qualities of wares.